What do theories tell us about how behaviour changes?

Abstract

Background: The aims of this study were (i) to identify frequently occurring mechanisms of action cited in behaviour change theories, and (ii) to describe these mechanisms in terms of what they change using the COM-B model: capability, opportunity, motivation and/or behaviour. Methods: The constructs from 83 theories of behaviour change were classified according to whether they were mechanisms of action (mediators of behaviour change) and, if so, further classified according to the COM-B model of behaviour using a card-sort task. Findings: 1376 constructs representing mechanisms of action were identified following the exclusion of constructs that related to demographics/prior experience, were moderating factors (e.g. public policy), or had definitions that were too broad. The majority fell within the category of ‘reflective motivation’, and the fewest within ‘physical capability’. Discussion: The majority of mechanisms of action from behaviour change theories can be described in terms of reflective processes (involving plans/evaluations), while the fewest relate to physical capabilities/skills. By identifying the most frequently occurring mechanisms, this research may facilitate the selection of target constructs for interventions.